1. Field of the Invention
The present invention relates to an apparatus for forming an image on a recording material, and more particularly to an image forming apparatus capable of reading image data from an external recording medium and forming a corresponding image on the recording material.
2. Related Background Art
In the related field, there are already commercialized analog image forming apparatus for optically scanning an original, equipped with an inverting mechanism for the recording sheet and capable of forming images on both sides of the recording sheet or forming multiple images on a side thereof by inverting or not inverting the sheet according to the instruction of an operation unit.
Such apparatus has enabled one to obtain a preformatted image or images on one side or both sides of the recording sheet by scanning a format image sheet, containing particular logos or charts consisting of horizontal and vertical lines. It is thus made possible to obtain a form overlay image of a predetermined format and an original image, by transferring the image of the original onto the predetermined format, by utilizing the above-mentioned sheet inverting mechanism.
However, in case of forming the format on the recording sheet by means of the format image sheet as explained above, it is necessary to prepare a format sheet and a corresponding original, and to conduct the exposure operation twice before the final image is obtained, so that the operation is quite complex.
Also the format sheet has to be exposed every time, so that the sheet is often smeared or creased according to the frequency of use thereof and has to be carefully stored and handled.